Emergence of Collective Organizational Phenomena in Manybody Systems

多体系统中集体组织现象的出现

• 批准号: 1607544
• 负责人: Deborah Watson
• 金额: $ 20.55万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1607544&HistoricalAwards=false
• 关键词: Emergence; Collective; Organizational; Phenomena; Manybody

The connection between the quantum world controlled by microscopic forces and the macroscopic world that dominates our everyday lives is not well understood. Macroscopic systems exhibit universal behavior that cannot depend sensitively on microscopic details, but is believed to be subject to powerful and general principles of organization. Universal behavior is seen in a variety of systems of interest across many branches of physics including the quark-gluon plasma of the early universe, high temperature superconductivity and ultracold Fermi gases in the laboratory. In this project, the P.I. will investigate the emergence of these powerful forces that give rise to the collective behavior of macroscopic systems. The plan is to perform a systematic study of properties as a function of system size, focusing on an intermediate regime called the mesoscopic region where quantum mechanics and classical mechanics merge. Both undergraduate and graduate students will participate fully in this research, including communicating the results through papers and talks.The scientific goal of this study is to elucidate the driving forces behind this emerging universal behavior and to propose new ways to observe and control this behavior in the laboratory. In the last decade, the atomic physics community has taken advantage of cooling and trapping techniques to create and control finite-size systems of ultracold gases that exhibit universal properties. This work will focus on Fermi gases and utilize a perturbation method that yields exact first-order results for all system sizes simultaneously. By studying trends as a function of system size for properties such as excitation frequencies and thermodynamic quantities recently measured in the laboratory, the goal is to uncover signatures of emerging collective behavior in order to understand the dynamics of this fundamental transition.

由微观力量控制的量子世界与主导我们日常生活的宏观世界之间的联系并不能很好地理解。宏观系统表现出普遍的行为，不能敏感地取决于微观细节，但被认为受组织的强大和一般原则的影响。在许多物理学分支的各种感兴趣系统中都可以看到普遍的行为，包括早期宇宙的夸克 - 胶状等离子体，高温超导性和实验室中的超低费米气体。在这个项目中，P.I.将研究这些强大力量的出现，这些力量引起了宏观系统的集体行为。该计划是针对系统大小的系统进行系统研究，重点是一种称为介质区域的中级政权，其中量子力学和经典力学合并。本科生和研究生都将充分参与这项研究，包括通过论文和谈话来传达结果。这项研究的科学目标是阐明这种新兴的普遍行为背后的驱动力，并提出新的方法来观察和控制实验室中的这种行为。 在过去的十年中，原子物理界利用了冷却和捕获技术来创建和控制具有通用性能的超速气体的有限大小系统。这项工作将集中在费米气体上，并利用一种扰动方法，该方法同时为所有系统尺寸提供确切的一阶结果。通过研究趋势是系统大小的函数，用于诸如最近在实验室中测量的激发频率和热力学量之类的属性，目的是发现新兴集体行为的签名，以了解这种基本过渡的动态。